Suspense is being uncertain of what is going to happen . In the film world it keeps you on the edge of your seat, wondering whats going to happen next.Suspense is similar to tension and can be built many different ways. For example non diegetic, music overplaying in an important and crucial scene will help to build the tension and keep you wondering.
An example where suspense is used in a film is 'Sabotage'. We are constantly wondering if Stevie is going to make it off the bus and deliver the bomb in time. Alfred Hitchcock cleverly plays ticking noises;like a clock, over the top of these scenes to create tension and build the suspence.
'Luck is everything... My good luck in life was to be a really frightened person. Im fortunate to be a coward to have a low threshold of fear, because a hero couldn't make a good suspense film.' - Alfred Hitchcock
Shock is something suddenly happening, for example a bomb explosion, crash etc. There is no tension or atmosphere to be built up to this moment, because as an audience we are unaware anything is going to happen and are just as surprised as the characters within the film.
An example of where shock is used is in a film called ' Children of Men'. A male character enters a shop to buy coffee whilst everyone is crowded around the T.V watching the news. He leaves the shop and as the camera slowly moves around we see the shop he was just in, blow up. This is a shock to us because we didn't know there was any bomb planted.